The invention relates generally to disk drives and the components thereof. More specifically, the invention relates to methods for the attachment of magnetic recording heads to disk drives using only one type of connection technology for both mechanical and electrical connections.
Assembly of the various component parts of any disk drive can be a complex task. Concerns such as mechanical and electrical integrity are often at issue. Disk drive components must be assembled to withstand extreme operating conditions such as high temperature and mechanical stress. Even still, the economic pressures on this technology also require that drives be assembled in a manner that is both efficient and affordable.
One critical element of the disk drive is the magnetic recording head. Without the head, the drive cannot read from, or write to, magnetic media. At the same time, the design of the head embodies both mechanical and electrical criticalities. For example, the head has at least one surface that is patterned and contoured to float above the disk. Additionally, the head must have the necessary electrical integrity to process the subject information.
In the past, disk drive assembly has relied upon adhesives to attach the top (opposite the air bearing surface) of the head to the suspension and solder or metal balls to electrically connect the end bond pads. Other systems used bond pads on the top surface to provide electrical and mechanical connections, but did not use leading edge pads. One example of such magnetic head assembly configuration is Kudo et al., U.S. Pat. No. 5,657,186. Kudo et al. disclose the use of gold contact balls to connect terminals and electrodes between the head assembly and the substrate.
Similarly, Endo et al., U.S. Pat. No. 5,696,651 teaches the use of gold to make electrical connections between the thin film head element and the suspension. Scheidecker et al, U.S. Pat. No. 5,734,523, also discloses the combined use of adhesive to attach the head assembly to the suspension arm and various solders to complete electrical connections. Arya et al., U.S. Pat. No. 5,889,636, discloses a similar system of head assembly attachment using both solder wire bumping and adhesive to attach solder to tongue. Frater et al., U.S. Pat. No. 5,680,275, discloses the use of solder as a form of attachment and as a spacer between the head assembly and the suspending arm.
However, the use of adhesives or a combination of adhesives and solder can make for a complicated system of assembly. As a result, there is a need for a simpler manner of forming the mechanical and electrical connections between the head and suspension.
In accordance with one aspect of the invention there is provided a suspension gimbal-head assembly that includes a magnetic head, having a leading edge and a following edge that is mechanically connected to the suspension gimbal at the head leading edge and the head following edge.
In accordance with another aspect of the invention there is provided a disk drive that includes a suspension gimbal-head assembly that includes a magnetic head having a leading edge and a following edge, a suspension gimbal, the magnetic head electrically connected to the suspension gimbal at the head leading edge and the head following edge.
Magnetic recording heads and suspension gimbals are assembled using a novel system that includes leading edge bond pads and corresponding bond pads on the suspension assembly. This differs from prior systems by allowing a common connection technology to be used for mechanical and electrical connections between the head and the suspension without the need for top bond pads.
Further, the invention allows the use of solders or metal contact balls avoiding the use of conductive adhesives. Conductive adhesives do not provide the same level of conductivity as metal contact balls or solder. The invention also provides better connection to ground, avoiding floating charges. The solder connections also allow easier reworking unlike adhesives, which often require chemical dissolution.